Well I went and got my car dynoed this morning and am a little pissed at the results. I ran my custom 8 lb. pulley first and actually got worse results because the car was pretty hot so we let the car cool down and put the 7 lb. pulley on and well here are the results. 296 rwhp 264 rwtq



The car barely saw 6 lbs. of of boost with the 7 lb. pulley so I don't know what's up. Boost leak? Belt slippage? I'm really ticked so if anyone has any input I would really appreciate it.

Hank

 

its time to sell that stage 3 pulley

 

Did you check for belt dust? Maybe u just need a smaller SC pulley or a larger crank pulley.

 

I'm about to sell the whole damn kit and go turbo.

 

really man? i think you might have a boost link or somthing?

 

Yeah I didn't notice any belt dust. Really I think maybe heat was the problem it was pretty warm up in Sacramento today. The second pull with the smaller 8 lb. pulley was something rediculous like 275 rwhp so we let the car cool down for a while and put the larger 7 lb. pulley on and made 296 rwhp.

 

hank, where in napa do u live? my cousins live there? PS. when do u think think you will be able to selll that stage 3 pulley? (what color is the pulley btw?)


Thanks sooo much,
Jordan

 

Naw I'm just kind of frustrated right now. Me and my buddy took the car out for a spin with the 8 lb. pulley tonight after it cooled down and I was seeing over 7 lbs. on my boost gauge so I'm hoping it was just the heat. Still, Stillen claims over 300 rwhp with the stage 1 kit so even at 6 lbs. I should see more than 296 wtf?

 

yea, even during the sport z shoot out there was over 300 hp with the stage 3. I think that maybe your belt is sliping or that there is some issue?

 

Well right now I'm trying to sort this out so I'm not sure. Sorry I can't be more specific. If you ever come out this way let me know maybe we could meet up.

 

Hank, heat is a real killer with the stillen setup. The difference is huge, just wait until you take the car out for a spin early in the morning or on a cool night. With some good airflow you will notice the difference.

If I end up keeping the car I will be installing a water methanol injection setup. Probably the 150 psi dual injector setup from www.coolingmist.com .

 

Cool man thanks for the link. I may have to go this route as well. The guy that runs the shop where I dynoed the car didn't thnk the intercooler was very efficient. He said I should go with a larger one or just a big tank that you could put dry ice in.

 

The intercooler really isn't very efficient and does just about jack when you aren't moving at 60 mph on a cool day. The other thing is the Stillen hood is thicker than the stock one and will retain heat more.

It really is a battle with the eaton SC to keep the heat down. I think the WI is a great route to go, especially in conjunction with a the varis CF insert. The more vents we have in the bumper the better, especially if it is leading directly to the intake.

The mustang cobra guys with the eaton m90 have had great results with WI. It can even lower the incoming air to below ambient. If you mix with 10% methanol (which just happens to be windshield washer fluid) you will also get a octane boost. This puts an extra measure of safety to prevent you from running lean.

The setup I am planning is to run the pump to the windshield washer tank (you get the extra benefit of having a built in low fluid detector) and use the dual injectors with the 150 psi pump. That should give a great amount of atomization.

The WI is hooked to a pressure switch, which is mounted with a simple T- line to the tube coming from the back passenger side of the plenum. I was planning to set it at 4.5 psi. It keeps everything normal until you get on boost.

WI has been around for a long time and its effects are proven.


Also, unless you let the car cool down overnight, it wasn't enough. You would have needed to throw bags of ice on the SC to get anything meaningful. This system really relies on airflow.

 

I have a few questions for you that might shed some light on you're problems

-What boost gauge are you running? Where are you getting the boost signal from?

-What base line dyno numbers (from a previous stage 2 pull) are you comparing your custom 8lb pulley run to? Can you show us that graph?

-I'm assuming that you were using the consult tool when you were dynoing...right? I know that Stillen does all their pulls using the consult tool and only begins logging the pull when the water temp is at 185*F. You did mention the car was "hot"....what was the water temp for all your pulls?

-What kind of dyno did you do the pulls on? Was it the EXACT SAME DYNO that you did your previous pulls on? If not then the comparison is pretty much useless.

-Napa is a really neat place to live. I haven't been up in that area of cali yet.....but I know it gets really hot out there. What was the outside temp during your dyno run? The car's ecu will adjust timing and fuel all dependant on the intake air temp sensor readings. Do you have these readings?

-I can pretty much guarantee you that your stock fuel system is maxed out at this boost. Did you monitor the injector duty cycle? If so what was it?

-What were you're A/F readings at? You did have a wideband to monitor this right?

Here's my theory. All you did was bolt on a pulley to give you more boost on a system designed and tuned for a lower boost setting. Your injectors are maxed out, your fuel pump is not flowing enough fuel to the engine and you're probably detonating and the ecu is pulling your timing in an attempt to keep the engine in one piece. A few degrees of timing being pulled can equate to quite a few ponies being lost. On to of all this your ecu isn't tuned for that amount of boost. Your engine is likely running very lean, and all the added heat from this is making the intercooler worthless. You need to upgrade the rest of your FI system to take advantage of your custom pulley. If you keep that pulley on there you're pretty much driving a time bomb. Sorry to be so blunt and upfront, but I'd hate to see you blow your engine.

sean

 

I dyno'd with the AF and never went over 12.2, I think that is still within the realm of safe. This was on a hot day and consistent even on the third pull. The stillen uses a large 7th injector that is capable of keeping up with the 8 lb pulley. People using more boost have gone to a larger 7th injector with walbro fuel pump.

I think it is pretty safe, especially with the conservative tuning of the stillen.

Heat is a problem though. Thus the WI.

 

Boost Gauge is a Defi-D. It is hooked up directly to the tap on the back of the Stillen manifold.

No baseline numbers. This is the first time I have dynoed the car.

No consult tool and not sure what the water temp was. It was about 90 degrees outside.

It was a dynojet.

I only used the AEM wideband gauge in the car to monitor A/f and at WOT it went to 11.2 with the 8 lb. pulley.

Like I said the 296 rwhp I made was on the Stillen stage three 7 lb. pulley and only saw 6 lbs. of boost.

 

K.
You have headers right? That = lost back-pressure which intern = lost hp.
Slap on your stock manifolds & you'll see more boost(guaranteed).
That's not the only problem.
Look at 4500rpm, there is a sudden drop. That is most likely due to detonation/ping. The ecu pulled timing at that point.Stillen did tune conservitavely but they maxed out the existing components doing so.
I logged duty cycle on my 7th injector & it was almost maxed out with 7lbs.
Stillen did this for a reason, so you guys wont "F" with it. Your fuel pump & 7th injector needs to be upgraded,then your piggy back needs to be custom tuned.

Another weird thing happened to me when I was on the dyno. My brake fluid was low & previous to the dyno my brake light kept coming on.When my car went on the dyno it was lifted in the back which shifted the little amount of brake fluid that I had left to the front of the fluid resevoir.
I believe that when my abs checked the lines(everytim you start your car the abs checks the lines), it sensed that there was no brake fluid.
This may have put my motor into limp mode on the dyno. At 4500rpm there was a sudden drop(sort of like yours).
That is only one of my guesses my car acted the way it did that day.
I was only running the 7lb pulley on my dyno day but the week before I had tried a 10lb pulley which made my car go into limpmode.
My buddy swears that something happened to my motor that day but I was in denial because a few days after the dyno day I whooped on a corvette

Wes

 

Yeah I was wondering about that dip at 4500. I was really hoping to not have to remove the headers but I think I will do that and see what happens.

 

That would be a really interesting post to see. I've wondered about that too.
Stillen has always said "No Headers" with their SC but never explained in detail what and why.

 

Yeah I will keep you guys posted on the results.